How much longer can Bashar al-Assad stay in power? Photograph: Muzaffar Salman/AP

This has been a tragic year for dictators. Gaddafi and Kim Jong-il are dead, Mubarak and Ben Ali ousted. In Yemen, Saleh is neither obviously in power nor out; Assad and Putin face stiff pressure and Hu Jintao will step aside peacefully, sustaining the party's power but not his own.

More successfully, the Saudi and Bahraini royal families have bought off resistance at least for now. Is there something in the air or is there something systematic behind the fall of so many dictators? Will 2012 see more of the same?

To understand why dictators fall it helps to recognise factors that produce a perfect anti-dictatorial storm. Barring missteps such as those that led to Gaddafi's undoing, a dictator's survival can be at risk because of newness in office, poor health or old age combined with economic trouble. Give people a bit more freedom and there is bound to be trouble.

Dictators, unlike democrats, depend on a small coterie to sustain their power. These backers, generally drawn from the military, the senior civil service, and family or clan members, have a synergistic relationship with their dictator. The dictator delivers opportunities for them to become rich and they protect him from being overthrown.

To meet his end of the bargain, the dictator must know where the money is and how to ensure that it flows to these essential backers. The money's delivery is at risk if the dictator is new (and so doesn't know where the money is) or is so old or unwell that he cannot be considered a long-term source of support.

Equally dangerous is a lack of money produced by an economy struggling with high unemployment, especially when concentrated among relatively well-educated people. These are the folks who must be kept happy enough that they don't organise a vocal opposition.

With a global economic downturn, falling oil prices, and lots of old and sick dictators, 2011 provided a great opportunity for political change. The coming year is likely to see the consolidation of power by some successor governments, few real shifts to democracy, and more turmoil in Syria, Russia and maybe Venezuela (where Chavez is rumoured to be terminally ill) or elderly Raul Castro's Cuba.

North Korea's Kim Jong-un could suffer in 2012 from not knowing where the money is, but that is unlikely. In Kim Jong-un's case we are more likely to see the effectiveness of dynastic dictatorship. Kim Jong-il surely entrusted his son with knowledge of where the money is. However ill-prepared Kim Jong-un is for leadership, if he knows where the money is he will do just fine.

Assad's Syria faced high unemployment and declining revenue from limited oil reserves. Shortage of money can be a formula for rebellion and reform but Assad has found new money in a bailout from Iran, Iraq and Venezuela. They are pumping billions of pounds into his regime, giving him the money to assure the senior military – just about all of them from his Alawite ruling coalition – that he can take care of them at least for now. Should the money run dry, then either Assad will liberalise or someone else will replace him and do so.

The greatest puzzle is Gaddafi's blundering in Libya after more than four decades in power. Maybe he believed his own propaganda and thought the people actually loved him. In his final few years he educated the people better than in neighbouring states – even though he didn't need an educated labour force given Libya's huge oil wealth. He even cut back on torture, perhaps to curry favour with Europe and the US. And he granted some press freedom.

This set the stage for anti-government factions to coordinate a rebellion, further fuelled by the contagious impact of seeing revolution succeed in the neighbourhood. Sadly, there is nothing about Libya's economy or the structure of its rebellion to inspire confidence in liberalisation and democratisation. More likely, the new Libyan regime will differ from Gaddafi's only in who it represses and abuses.

As for Russia and China, they are likely to continue to muddle through. Only a collapse in oil prices is likely to produce real change in Russia. China may be moving towards uprising or fundamental internal political change. As the people in the coastal provinces grow rich they also grow restive and want a greater say in what happens to their wealth. The people in the poor western and northern provinces are growing impatient – in their case with their failure to share in China's growing wealth. This is a combustible combination that eventually is likely to produce big change. It would be wise to watch for signs of rebellion kindling in 2012.